CN111032532A

CN111032532A - Steam flow through flat bag

Info

Publication number: CN111032532A
Application number: CN201880053139.9A
Authority: CN
Inventors: 下野贵裕
Original assignee: Toppan Printing Co Ltd
Current assignee: Toppan Inc
Priority date: 2017-08-16
Filing date: 2018-08-08
Publication date: 2020-04-17
Anticipated expiration: 2038-08-08
Also published as: TWI829644B; WO2019035399A1; CN111032532B; TW201910228A; US20200180843A1; JP2019034761A; JP6988255B2

Abstract

The steam flow-through flat bag comprises a sealing portion, a steam flow-through sealing portion, and a steam discharge portion. The sealing portion seals the overlapped sheets. The steam circulation seal portion joins portions of the sheets to each other so as to be discontinuous with respect to the seal portion at an inner portion of the sheet which is a portion inside the seal portion. The steam discharge portion is formed in the steam circulation seal portion so as not to communicate the housing space with the outside in a state where the steam circulation seal portion is not peeled, and so as to communicate the housing space with the outside in a state where the steam circulation seal portion is peeled. The steam circulation seal portion includes: a peeling-first portion including a portion that peels first as the pressure increases; and a post-peeling portion including a portion peeled last. The width of the post-peeling portion is smaller than the width of the pre-peeling portion.

Description

Steam flow through flat bag

Technical Field

The invention relates to a steam flow through flat bag.

Background

It is known that steam generated from the contents by heating flows through a flat bag to be discharged to the outside. Patent document 1 discloses an example of a current steam flow-through flat bag. As shown in fig. 11, the steam flow type flat bag (100) of patent document 1 includes: a laminate (150) that forms a storage space (110) for storing the contents; and a heat-fusion part (120) that bonds the stacked body (150) so as to close the housing space (110). The heat fusion part (120) is divided into: an outer peripheral portion (121) corresponding to the outer contour shape of the vapor flow-through flat bag (100); and a protruding portion (130) formed so as to protrude from the outer peripheral portion (121) toward the housing space (110). A notch (140) that communicates with the outside of the steam flow-through flat bag (100) in a state where the housing space (110) is closed by the heat-fusion part (120) is formed in a portion surrounded by the outer peripheral part (121) and the extension part (130). In a state where the extension part (130) joins the laminate (150), the extension part (130) seals the space between the storage space (110) and the notch (140), so that the contents of the storage space (110) do not move to the notch (140).

When the vapor flow-through flat bag (100) is heated by a heating means such as a microwave oven, the pressure of the storage space (110) is increased by the water vapor generated from the contents, and a force acting to peel the protruding section (130), in detail, the upper laminated body (151) and the lower laminated body (152) constituting the protruding section (130) is applied to the protruding section (130). When the pressure in the housing space (110) is increased to a certain level, as shown in fig. 12, a part of the extension portion (130) is peeled off, and the peeling of the extension portion (130) progresses toward the outer peripheral portion (121) of the heat-fusion bonded portion (120). As shown in fig. 13, when the peeling of the extension portion (130) reaches the notch (140), the housing space (110) and the outside of the steam flow-through flat bag (100) communicate with each other through the notch (140), and the water vapor in the housing space (110) is discharged to the outside through the notch (140).

Patent document 1: japanese laid-open patent publication No. 11-208739

Disclosure of Invention

According to the above-mentioned vapor flow type flat bag (100), in a state where the storage space (110) and the outside of the vapor flow type flat bag (100) communicate with each other through the slit (140), the upper laminated body (151) and the lower laminated body (152) are connected to the heat-fusion part (120) which is a part of the laminated body (150) where the slit (140) is formed. Therefore, the distance between the notch (140) and the content is short, and when the water vapor is discharged from the notch (140), the content may leak from the notch (140) together with the water vapor.

(1) The invention relates to a steam flow general flat bag comprising: a sealing portion that seals the sheets that are stacked so as to form a housing space for housing the contents; a steam circulation seal portion that joins portions of the sheet materials to each other so as to be discontinuous with respect to the seal portion, at an inner portion of the sheet material that is a portion inside the seal portion; and a steam discharge portion formed in the steam circulation seal portion so as not to communicate the housing space with the outside in a state where the steam circulation seal portion is not peeled and to communicate the housing space with the outside in a state where the steam circulation seal portion is peeled, the steam circulation seal portion including: a peeling-first portion including a portion that is peeled first at the steam flow seal portion in accordance with an increase in pressure of the housing space; and a post-peeling portion included in a portion of the steam circulation seal portion that is peeled last, a width of the post-peeling portion in a direction different from a development direction of the peeling of the steam circulation seal portion being smaller than a width of the pre-peeling portion in a direction different from the development direction of the peeling.

In the case where the steam flow-through flat bag whose housing space is closed by the seal portion is heated by the heating unit, in one example, one of the overlapped sheets is located below, and the sheet on which the steam discharge portion is formed as the other of the overlapped sheets is located above.

When the steam flow type flat bag is heated in this state, the pressure of the storage space is increased by the water vapor generated from the content, and a force acting to peel off the steam flow seal portion is applied to the steam flow seal portion. The pressure in the housing space is increased to a certain level, so that the steam circulation sealing part is peeled from the first peeling part, and the peeling of the steam circulation sealing part is progressed to the second peeling part. When the peeling of the steam circulation seal portion reaches the steam discharge portion, the housing space communicates with the outside by the steam discharge portion, and therefore the water vapor in the housing space is discharged to the outside through the steam discharge portion. Therefore, the pressure in the housing space can be suppressed from increasing, and the force acting to peel off the steam flow seal portion can be reduced. However, since the width of the post-peeling section is smaller than the width of the pre-peeling section, it is difficult to cause a situation in which the steam flow seal section stops peeling at a position on the front side of the end of the post-peeling section. When the peeling of the steam circulation seal portion reaches the end of the rear peeling portion, a portion of the upper sheet not joined by the steam circulation seal portion moves upward so as to be separated from the lower sheet and the content. In the above-described steam flow type flat bag, the steam flow seal portion is formed in the inner portion, and the steam discharge portion is formed in the steam flow seal portion, so that the steam discharge portion also moves upward so as to be separated from the sheet and the content below as the sheet above moves upward. Therefore, the contents are less likely to leak when the water vapor is discharged.

(2) In a preferred embodiment, on the basis of the steam flow-through flat bag described in (1), the rear peel portion is formed so as to decrease in width toward the front side in the development direction of the peel.

Therefore, when a force acting to peel off the steam flow seal is applied to the steam flow seal, local stress concentration is less likely to occur in the steam flow seal.

(3) In a preferred example, in the steam flow-through flat bag of (1) or (2), the steam vent includes a slit or a hole penetrating one of the overlapped sheets, and is formed to extend in a development direction of the peeling.

The hole or the slit does not communicate the accommodating space with the outside in a state where the peeling of the steam circulation seal portion does not reach the hole or the slit of the steam discharge portion. In a state where the peeling of the steam flow seal portion reaches the hole or the slit, the hole or the slit communicates the housing space with the outside, and as the peeling progresses, the area of a portion where the hole or the slit directly communicates with the housing space (hereinafter referred to as "communication area") increases. The above-described steam flow-through flat bag is formed in such a manner that the holes or slits extend in the direction of development of the peeling, and therefore the communication area gradually increases in accordance with the development of the peeling. Therefore, the flow rate of the steam discharged from the housing space to the outside can be prevented from increasing rapidly, and the steam flow seal portion can be easily peeled off to reach the end of the rear peeling portion.

(4) In a preferred embodiment, the steam flow-through flat bag according to any one of (1) to (3) further includes a guide portion constituting a guide for separating the sheet and a part of the seal portion so that the housing space closed by the seal portion opens a portion of the sheet separated by the guide portion, the portion being provided in the sheet, the portion being sealed by the seal portion.

Therefore, when the portion of the sheet separated by the guide portion (hereinafter referred to as "separation portion") is separated, the steam discharge portion does not remain in the portion of the sheet in which the content is contained, and when the content is taken out from the containing space, the content does not leak from the steam discharge portion.

(5) In a preferred embodiment, in the steam flow-through flat bag according to any one of (1) to (4), a dimension of the steam discharge portion in a development direction of the peeling is 12.5% or more of a dimension of the steam flow-through seal portion in the development direction of the peeling.

When the size of the steam discharge portion is within the above range, the steam is appropriately discharged from the steam discharge portion when the accommodating space communicates with the outside through the steam discharge portion.

(6) In a preferred embodiment, in the steam flow-through flat bag according to any one of (1) to (5), the size of the steam escape part in the development direction of the peel is less than or equal to 62.5% of the size of the steam flow-through seal part in the development direction of the peel.

When the size of the steam discharge part is included in the above range, foreign substances are less likely to enter the steam discharge part.

(7) In a preferred embodiment, the steam flow type flat bag according to any one of (1) to (6) further includes the content stored in the storage space.

Effects of the invention

According to the steam flow type flat bag of the present invention, the contents are less likely to leak when the steam is discharged.

Drawings

Fig. 1 is a front view of a steam flow-through flat bag according to an embodiment of the present invention.

Fig. 2 is an enlarged view of the steam flow seal part of fig. 1 and its surroundings.

Fig. 3 is a front view of a vapor-flow flat bag before the opening is closed.

FIG. 4 is a front view of the steam flow-through flat bag of FIG. 1 with a portion of the steam flow seal peeled away.

FIG. 5 is a front view of the steam flow-through flat bag in a state where the entire steam flow seal part of FIG. 4 is peeled.

Fig. 6 is a sectional view taken along line D6-D6 in fig. 5.

FIG. 7 is a table showing test conditions of comparative examples and examples related to the test.

FIG. 8 is a table showing test results of comparative examples and examples.

Fig. 9 is an enlarged view of a steam flow seal part and its surroundings according to a modification.

Fig. 10 is an enlarged view of a steam flow seal part and its surroundings in a modification.

Fig. 11 is a front view of a current steam flow-through flat bag.

Fig. 12 is a sectional view taken along line D12-D12 in fig. 11.

Fig. 13 is a sectional view of the state in which the extension portion of fig. 12 is peeled off.

Detailed Description

(embodiment mode)

Fig. 1 shows an example of a steam flow type flat bag 10 capable of accommodating contents C suitable for heating and discharging steam generated from the contents C. The content C generates water vapor due to heating. An example of the content C is a food. An example of a food product is a heat-cooked food product. An example of this is the food material of beef rice, hamburgers and stews. The steam flow type flat bag 10 is configured to ensure the quality of the content C and to be stored for a long period of time.

The steam flow type flat bag 10 includes a sheet 20, a sealing portion 30, an opening portion 40 (see fig. 3), a guide portion 50, a steam flow sealing portion 60, and a steam discharge portion 70. The dots in fig. 1 and the like indicate the seal portion 30 and the steam flow seal portion 60. The sheet 20 includes a 1 st sheet 21 and a 2 nd sheet 22. The 1 st sheet 21 and the 2 nd sheet 22 are opposed to each other so that a housing space 10C for housing the content C is formed between the

sheets

21 and 22. The structure of the sheet 20 may be arbitrarily selected. In example 1, the

sheets

21 and 22 are 2 sheets formed separately. In example 2, 1 sheet is folded to form

opposed sheets

21 and 22.

The sheet 20 (each of the sheets 21 and 22) has a layered structure in which a plurality of layers are stacked. The layered configuration of the sheet 20 (each sheet 21, 22) may be arbitrarily selected. In example 1, the

sheets

21, 22 have the same layered structure as each other. In example 2, the 1 st sheet 21 and the 2 nd sheet 22 have different layered configurations. A steam flow-through flat bag 10 constructed from sheet 20 having the layered construction of example 1 is shown in fig. 1.

Each

sheet

21, 22 includes an outermost layer, an intermediate layer, and an innermost layer. An example of a method of manufacturing each of the

sheets

21 and 22 is a dry lamination method. The outermost layer is mainly excellent in gloss, printability and retort resistance. Here, the boiling resistance refers to resistance to a boiling treatment. One example of a material constituting the outermost layer is a transparent material. An example of a transparent material is polyethylene terephthalate. The intermediate layer mainly has excellent boiling resistance, moisture resistance and gas barrier properties. The middle layer comprises a printing layer, a 1 st adhesive layer, a stretched nylon layer and a 2 nd adhesive layer. The printing layer is arranged on the inner side of the outermost layer. In one example, a pattern, a text of a commercial description, or the like is printed on the outer surface of the printed layer. The 1 st adhesive layer is provided on the inner side of the printed layer. The tensile nylon layer is arranged on the inner side of the 1 st bonding layer. The 2 nd adhesive layer is arranged on the inner side of the stretched nylon layer. An example of a material constituting each adhesive layer is a dry lamination adhesive. The innermost layer has excellent retort resistance, heat sealability and impact resistance. The innermost layer is arranged on the inner side of the 2 nd adhesive layer. One example of a material constituting the innermost layer is unstretched polypropylene.

The sealing portion 30 joins the

sheets

21 and 22 so that the

sheets

21 and 22 are not separated from each other. In one example, the seal portion 30 joins the innermost layer of the 1 st sheet 21 and the innermost layer of the 2 nd sheet 22. An example of a method of forming the seal portion 30 is a heat sealing method. The shape of the exterior profile of the steam flow-through flat bag 10 in the main view can be chosen arbitrarily. In the example shown in fig. 1, the exterior profile of the steam flow-through flat bag 10 is rectangular in shape. The sheet 20 can be divided into a portion surrounded by the seal portion 30 (hereinafter referred to as "inner portion 23") and the seal portion 30. The housing space 10C is a space surrounded by the inner side portion 23 of the 1 st sheet 21 and the inner side portion 23 of the 2 nd sheet 22, and is closed by the seal portion 30 so as not to communicate with the outside of the steam flow-through flat bag 10.

The seal portion 30 joins the 1 st sheet 21 and the 2 nd sheet 22 so as to close the housing space 10C. The seal portion 30 is divided into the 1 st seal portion 31 to the 4 th seal portion 34. The 1 st seal portion 31 is formed along the 1 st edge 20A of the sheet 20. The 2 nd seal 32 is formed along the 2 nd edge 20B of the sheet 20. The 3 rd seal 33 is formed along the 3 rd edge 20C of the sheet 20. The 4 th seal 34 is formed along the 4 th edge 20D of the sheet 20. In order to accommodate the contents in the housing space 10C, the 1 st seal portion 31, the 3 rd seal portion 33, and the 4 th seal portion 34 are formed before the 2 nd seal portion 32. In a state where the 1 st, 3 rd, and 4

th seal parts

31, 33, and 34 are formed and the 2 nd seal part 32 is not formed, an opening 40 (see fig. 3) for pouring the contents into the housing space 10C is formed in the steam flow-through flat bag 10. After the contents are put into the housing space 10C, the 2 nd sealing part 32 is formed, and the opening 40 is closed by the 2 nd sealing part 32. Hereinafter, in the front view of the steam flow-through pouch 10, the direction along the 1 st side 20A and the 2 nd side 20B is referred to as the 1 st direction, and the direction along the 3 rd side 20C and the 4 th side 20D is referred to as the 2 nd direction.

The inner edge 31A of the 1 st seal portion 31, which is the edge on the inner portion 23 side, the inner edge 32A of the 2 nd seal portion 32, which is the edge on the inner portion 23 side, the inner edge 33A of the 3 rd seal portion 33, which is the edge on the inner portion 23 side, and the inner edge 34A of the 4 th seal portion 34, which is the edge on the inner portion 23 side, define the outer contour of the inner portion 23. The outer edge 31B of the 1 st seal portion 31, which is the edge on the opposite side from the inner edge 31A, the outer edge 32B of the 2 nd seal portion 32, which is the edge on the opposite side from the inner edge 32A, the outer edge 33B of the 3 rd seal portion 33, which is the edge on the opposite side from the inner edge 33A, and the outer edge 34B of the 4 th seal portion 34, which is the edge on the opposite side from the inner edge 34A, define the outer contour of the steam flow-through flat bag 10.

The width of each seal part 31-34 can be arbitrarily selected. The width of each of the seal portions 31 to 34 is the length between the inner edges 31A to 34A and the outer edges 31B to 34B on the normal line of the center line of each of the seal portions 31 to 34. The center lines of the sealing portions 31 to 34 are virtual line segments passing between the inner edges 31A to 34A and the outer edges 31B to 34B. In the case where the width of each of the seal portions 31 to 34 differs for each portion, for example, the maximum width or the average value of the widths of a plurality of portions of each of the seal portions 31 to 34 represents the width of the seal portion.

The dimensions of the steam flow type flat bag 10 in the 1 st direction and the 2 nd direction are preferably determined in accordance with, for example, the relationship with the amount of the content C to be stored and the ease of carrying the steam flow type flat bag 10. The dimension in the 1 st direction of the steam flow-through flat bag 10 is the length between the outer edge 33B of the 3 rd seal part 33 and the outer edge 34B of the 4 th seal part 34 on the line segment orthogonal to the 2 nd direction. In the case where the dimension of the flow-through pouch 10 in the 1 st direction differs for each site, for example, the maximum dimension or the average of the dimensions of a plurality of sites represents the dimension of the flow-through pouch 10 in the 1 st direction. According to one example, the 1 st dimension of the steam flow-through flat bag 10 is 130 mm. The dimension in the 2 nd direction of the steam flow-through flat bag 10 is the length between the outer edge 31B of the 1 st seal part 31 and the outer edge 32B of the 2 nd seal part 32 on the line segment orthogonal to the 1 st direction. In the case where the dimension in the 2 nd direction of the steam flow-through flat bag 10 differs for each site, for example, the maximum dimension or the average of the dimensions of a plurality of sites represents the dimension in the 2 nd direction of the steam flow-through flat bag 10. According to one example, the 2 nd dimension of the steam flow-through flat bag 10 is 135 mm.

An opening 40 (see fig. 3) is formed between the lower portion 21A of the 1 st sheet 21 and the lower portion 22A of the 2 nd sheet 22 so that the storage space 10C can be filled with the contents C. In the case of the steam flow-through pouch 10 shown in fig. 1, the opening 40 is closed by the 2 nd seal 32. The steam flow type flat bag 10 having the closed opening 40 (hereinafter referred to as "closed steam flow type flat bag 10") includes a bag main body 10A and a separation part 10B. The bag body 10A and the separating portion 10B are defined by a cutting line 51 constituting the guide portion 50. The bag main body 10A is a portion for containing the content C. The separating portion 10B is a portion of each of the

sheets

21 and 22 including the 1 st sealing portion 31, and is a portion separated from the bag main body 10A by a user in order to take out the content C from the housing space 10C.

The guide portion 50 is formed between the bag body 10A and the separating portion 10B to easily cut the

sheets

21, 22, respectively, when the separating portion 10B is separated from the bag body 10A. The guide portion 50 has a cutting line 51 and a notch 52. The cutting line 51 is a set of perforations formed in the sealing

portions

33 and 34 and the inner portions 23 of the

sheets

21 and 22, and is formed linearly. The notch 52 is formed in at least one of the 3 rd seal portion 33 and the 4 th seal portion 34 such that a tip end portion of the notch 52 is positioned on a virtual line extending from the cutting line 51. Fig. 1 shows an example in which notches 52 are formed in the 3 rd seal part 33 and the 4 th seal part 34, respectively.

The steam flow-through flat bag 10 is heated by a heating unit (heating device) in order to heat the content C. An example of a heating unit is a microwave oven. Water vapor is generated from the contents C as the vapor stream is heated through the flat bag 10. The storage space 10C of the closed steam flow-through flat bag 10 is closed by the seal portion 30, and therefore the pressure of the storage space 10C rises with the generation of water vapor.

The steam flow seal 60 is a portion of the inner portion 23 in which the innermost layer of the 1 st sheet 21 and the innermost layer of the 2 nd sheet 22 are joined, and is configured to peel the innermost layer of the 1 st sheet 21 and the innermost layer of the 2 nd sheet 22 as the pressure in the housing space 10C increases. Hereinafter, the "peeling of the steam flow seal portion 60" means that the innermost layer of the 1 st sheet 21 and the innermost layer of the 2 nd sheet 22 constituting the steam flow seal portion 60 are peeled. In a preferred embodiment, the steam flow seal portion 60 is configured to be peeled off when the pressure in the housing space 10C is increased to a pressure within a predetermined pressure range. The steam discharge unit 70 communicates the housing space 10C with the outside of the steam flow-through flat bag 10 when the steam flow seal 60 is peeled off, and discharges the steam generated from the content C to the outside of the steam flow-through flat bag 10. The steam is discharged from the steam discharging part 70, thereby suppressing the pressure rise of the housing space 10C and avoiding the steam flow through the flat bag 10 from being broken. The steam discharge part 70 is provided inside the outer contour of the steam flow seal part 60.

The steam circulation seal portion 60 is provided discontinuously with respect to the seal portion 30. Since the steam flow seal portion 60 is separated from the seal portion 30, the steam discharge portion 70 may be formed in the sheet 20 at a position separated from the seal portion 30. The number of the steam flow seal portions 60 provided in the inner portion 23 is 1 or more. The steam flow seal 60 is provided at any position of the inner portion 23. In a preferred embodiment, the steam flow seal portion 60 is provided at a location where strong stress concentration occurs when the pressure in the housing space 10C is increased. In example 1, the steam flow seal portion 60 is provided at a position facing the center in the longitudinal direction of the 1 st seal portion 31 in the separation portion 10B. In example 1, when the separating portion 10B is separated from the bag main body 10A, the steam flow seal portion 60 does not remain in the bag main body 10A, and when the content C is taken out from the housing space 10C, the content C does not leak from the steam discharging portion 70. In example 2, the steam flow seal part 60 is provided in the bag body 10A.

Fig. 2 is an enlarged view of the steam flow seal portion 60 and its surroundings. The outer contour shape of the vapor communication seal 60 may take various shapes. An example of this is a triangle, a shape similar to a triangle, a trapezoid, a shape similar to a trapezoid, and a convex shape. In the illustrated example, the outer contour of the steam flow seal 60 is shaped as an isosceles triangle. The sides constituting the isosceles triangle are the 1 st and 2

nd sides

60A and 60B as the equilateral sides, and the 3 rd side 60C as the base side. The seal width XA of the steam flow seal portion 60 is a distance between the 1 st side 60A and the 2 nd side 60B in the 1 st direction.

When the pressure in the housing space 10C is increased by heating the steam flow-through flat bag 10, the steam flow seal 60 is peeled off, and the peeling of the steam flow seal 60 progresses with the increase in pressure. When the peeling of the steam flow seal portion 60 reaches the steam outlet portion 70, the housing space 10C and the outside of the steam flow-through flat bag 10 communicate with each other through the steam outlet portion 70. The area of the portion of the steam discharge portion 70 that directly communicates with the housing space 10C, that is, the communication area of the steam discharge portion 70 increases as the separation of the steam flow seal portion 60 progresses. When the pressure in the housing space 10C is assumed to be constant, the flow rate of the steam to be discharged to the outside of the steam flow-through flat bag 10 via the steam discharging unit 70 increases as the communication area of the steam discharging unit 70 increases. The communication area is 0 in a state where the steam flow seal portion 60 is not peeled and in a state where the peeling of the steam flow seal portion 60 does not reach the steam discharge portion 70. When the entire portion around the steam discharge portion 70 in the steam flow seal portion 60 is peeled off, the communication area is maximized.

The steam circulation seal portion 60 includes: a peeling-first section 61 including a portion which is peeled first in the steam flow seal section 60; and a rear peeling part 62 included in a portion where the steam circulation sealing part 60 is peeled off last. In the illustrated example, the portion of the steam flow seal 60 that is peeled off first is a part or all of the 3 rd side 60C. The portion of the steam flow seal portion 60 that is peeled off last is the apex 60D. The seal width XA of the rear peeling part 62 in the direction different from the direction of progress of peeling of the steam flow seal part 60 is smaller than the seal width XA of the front peeling part 61 in the direction different from the direction of progress of peeling of the steam flow seal part 60. An example of a "different direction" is a cross direction, in the preferred embodiment an orthogonal direction.

The peeling-first section 61 includes, for example, the following sections in the steam flow seal section 60. In example 1, the preliminary peeling portion 61 includes a portion extending from the 3 rd side 60C of the steam flow seal portion 60 to the steam discharge portion 70. In example 1, the preliminary peeling portion 61 does not include an end portion of the steam discharge portion 70 on the side of the storage space 10C (hereinafter referred to as an "inner end portion of the steam discharge portion 70"). When the range of the pre-peeling portion 61 is the range of example 1, the steam discharge portion 70 does not communicate with the storage space 10C until the peeling of the steam flow seal portion 60 reaches the peeling portion 62. In a state immediately after the peeling of the steam flow seal portion 60 reaches the steam discharge portion 70, the communication area is small, so that the force acting to peel the steam flow seal portion 60 is large, and the peeling of the rear peeling portion 62 progresses smoothly following the peeling of the front peeling portion 61. In example 2, the preliminary peeling portion 61 includes a portion from the 3 rd edge 60C to the inner end of the steam discharge portion 70. In example 2, the preliminary peeling portion 61 includes an inner end portion of the steam discharge portion 70. When the range of the pre-peeling section 61 is the range in example 2, the inner end of the steam discharge section 70 directly communicates with the accommodating space 10C in a state where the entire pre-peeling section 61 is peeled off, but the communication area of the steam discharge section 70 is small, and therefore, a state where the pressure of the accommodating space 10C is high is maintained. Therefore, a force acting to peel off the steam flow seal portion 60 is large, and peeling of the rear peeling portion 62 progresses smoothly after peeling of the front peeling portion 61.

The steam discharge part 70 may take various structures. According to example 1, the steam discharge portion 70 is a slit or a hole penetrating the 1 st sheet 21. According to example 2, the steam discharge portion 70 is a slit or a hole through which the 1 st sheet 21 does not penetrate. The depth of the notch or the depth of the hole in example 2 is preferably such a depth that the portion of the 1 st sheet 21 corresponding to the steam discharge portion 70 is broken when the steam flow seal portion 60 has been peeled off. The steam discharge part 70 may take various outer contour shapes. According to example 1, the outer contour shape of the steam discharge part 70 is a rectangle extending in the 1 st or 2 nd direction. According to example 2, the outer contour shape of the steam discharge part 70 may be an equilateral triangle, an isosceles triangle, a square, or a polygon having five or more sides. In a state where the peeling of the steam flow seal portion 60 does not reach the hole or the slit of the steam discharge portion 70, the hole or the slit does not communicate the housing space 10C with the outside. In a state where the peeling of the steam flow seal portion 60 reaches the hole or the slit, the hole or the slit communicates the housing space 10C with the outside, and the peeling progresses, and a communication area as an area of a portion of the hole or the slit communicating the housing space 10C with the outside increases.

In example 1 or example 2, in the case where the outer contour shape of the steam discharge portion 70 is formed to extend in the direction of progress of the peeling of the steam flow seal portion 60 (hereinafter referred to as "peeling progress direction"), the communication area gradually increases in accordance with the degree of progress of the peeling. Therefore, the flow rate of the steam discharged from the housing space 10C to the outside can be suppressed from increasing rapidly, and the peeling of the steam flow seal portion 60 is likely to reach the peak 60D which is the end of the rear peeling portion 62.

The ratio of the dimension HB of the steam vent part 70 in the direction of the progress of the peeling to the dimension HA of the steam flow seal part 60 in the direction of the progress of the peeling (hereinafter referred to as "vent part ratio RA") is preferably determined in accordance with the relationship with the degree of easy venting of the water vapor and the degree of difficulty in entry of foreign matters into the steam vent part 70. The equation for obtaining the discharge portion ratio RA is "RA ═ (HB/HA) × 100". The dimension HA is, for example, the height of the steam flow seal 60 when the outer contour of the steam flow seal 60 is triangular. The dimension HB is, for example, the length of the long side of the steam discharge portion 70 when the outer contour shape of the steam discharge portion 70 is rectangular. A preferable example of the maximum value of the discharge portion ratio RA is 62.5%. A more preferable example of the maximum value of the discharge portion ratio RA is 25%. In the case where the discharge portion ratio RA is 62.5% or less, it is difficult for foreign substances to enter the steam discharge portion 70. In the case where the discharge portion ratio RA is less than or equal to 25%, the foreign substances are more difficult to enter the steam discharge portion 70. A preferable example of the minimum value of the discharge portion ratio RA is 12.5%. A more preferable example of the minimum value of the discharge portion ratio RA is 25%. In the case where the discharge portion ratio RA is 12.5% or more, the water vapor is appropriately discharged from the vapor discharge portion 70 in the case where the vapor flow seal portion 60 has been peeled off. When the discharge portion ratio RA is 25% or more, the steam is more appropriately discharged from the steam discharge portion 70 when the steam flow seal portion 60 is peeled off.

Fig. 3 shows the steam-flow-through flat bag 10 before the opening 40 is closed (hereinafter referred to as "steam-flow-through flat bag 10 before closing"). The content C (see fig. 1) is put into the storage space 10C from the opening 40 of the steam-flow-through flat bag 10 before closing. After the contents C are charged, the portion to be sealed 80 where the 2 nd seal portion 32 is to be formed is heat-sealed, thereby forming the 2 nd seal portion 32, and the closed steam flow-through type flat bag 10 shown in fig. 1 is obtained.

Referring to fig. 1, an example of a method of using the steam flow type flat bag 10 will be described.

The steam flow type flat bag 10 in a closed state is placed on a heating means (not shown) such as a microwave oven so that the 2 nd sheet 22 is positioned below the 1 st sheet 21, and is heated by the heating means. After the heating is finished, the

respective sheets

21, 22 are torn from the front end portions of the notches 52, and the

respective sheets

21, 22 are urged so that the tearing of the

respective sheets

21, 22 progresses along the cutting line 51. The separating portion 10B is separated from the bag body 10A, and the content C is taken out from the storage space 10C to the outside of the steam flow type flat bag 10.

The function of the steam flow-through pouch 10 will be described with reference to fig. 4-6.

In the case of heating the steam flow-through flat bag 10 in a closed state by the heating means, in one example, the 2 nd sheet 22 is disposed below and the 1 st sheet 21 having the steam vents 70 formed therein is disposed above. When the steam flow-through flat bag 10 in the closed state is heated in this state, the pressure of the storage space 10C is increased by the water vapor generated from the content C, and a force acting to peel off the steam flow-through seal portion 60 is applied to the steam flow-through seal portion 60. The pressure in the housing space 10C is increased to a certain level, whereby the peeling of the steam flow seal portion 60 proceeds from the first peeling portion 61, and the peeling of the steam flow seal portion 60 progresses toward the second peeling portion 62. As shown in fig. 4, when the peeling of the steam flow seal portion 60 reaches the steam discharge portion 70, the housing space 10C communicates with the outside by the steam discharge portion 70, and therefore the steam in the housing space 10C is discharged to the outside through the steam discharge portion 70. Therefore, the pressure increase in the housing space 10C can be suppressed, and the force acting to peel off the steam flow seal portion 60 can be reduced. However, since the seal width XA of the rear peeling section 62 is smaller than the seal width XA of the front peeling section 61, it is difficult to cause a situation in which the peeling of the steam flow seal section 60 is stopped at a position closer to the front side than the end of the rear peeling section 62. When the peeling of the steam flow seal portion 60 reaches the end of the rear peeling portion 62 as shown in fig. 5, the portion of the 1 st sheet 21 joined by the steam flow seal portion 60 moves upward so as to be separated from the 2 nd sheet 22 and the content C as shown in fig. 6. In the steam flow type flat bag 10, the steam flow seal portion 60 is formed in the inner portion 23, and the steam discharge portion 70 is formed in the steam flow seal portion 60, so that the steam discharge portion 70 also moves upward so as to be separated from the 2 nd sheet 22 and the content C in accordance with the upward movement of the 1 st sheet 21. Therefore, the content C is difficult to leak when the water vapor is discharged.

(examples)

The inventors of the present application performed tests for confirming the relationship between the structures of the steam flow seal part 60 and the steam discharge part 70 and the seal peeling performance and the steam flow performance, using the samples of the examples and the comparative examples. FIG. 7 shows the test conditions of comparative examples and examples in connection with the test. Fig. 8 shows the test results. In the following description, for convenience of explanation, the portions of the comparative sample that communicate with the samples of the examples are labeled with the same reference numerals. The sample of the example is a vapor flow-through flat bag 10 according to the embodiment. The sample of the comparative example is a vapor flow-through flat bag 10 having a different structure from the vapor flow-through flat bag 10 of the example. The steam flow-through pouch 10 of each comparative example differs from the steam flow-through pouch 10 of the embodiment in that the seal width XA of the rear peel portion 62 in the direction of progress of the peel is larger than the seal width XA of the front peel portion 61 in the direction of progress of the peel, and has the same structure as the steam flow-through pouch 10 of the embodiment in other respects.

The parameters associated with each example and each comparative sample are as follows. The outermost layer of each

sheet

21, 22 is made of polyethylene terephthalate. The thickness of the outermost layer was 12 μm. The material constituting the intermediate layer of each

sheet

21, 22 is nylon. The thickness of the intermediate layer was 15 μm. The material constituting the innermost layer of each

sheet

21, 22 is unstretched propylene. The thickness of the innermost layer was 60 μm. The dimension in direction 1 of the steam flow through flat bag 10 is 130 mm. The dimension in direction 2 of the steam flow through flat bag 10 is 135 mm. The number of the steam flow seal portions 60 provided in the inner portion 23 is 1. The steam-fed flow seal portion 60 is provided at a position facing the center of the separation portion 10B in the longitudinal direction of the 1 st seal portion 31.

The outer contour shape of the vapor communication seal portion 60 of the samples of comparative example 1 and comparative example 5 was a circle. The radius of the circle is 5 mm. The samples of comparative examples 2 and 6 had square outer contour shapes of the vapor communication seal 60. The length of 1 side of the square is 10 mm. The outer contour shape of the vapor flow seal 60 of the samples of comparative examples 3 and 7 is a trapezoid in which the seal width XA increases from the center of the inner side portion 23 toward the 1 st seal portion 31, i.e., in the direction of the progress of peeling. The length of the upper bottom of the trapezoid is 10mm, the length of the lower bottom is 20mm, and the height is 10 mm. The outer contour shape of the vapor flow seal 60 of the samples of comparative examples 4 and 8 is an equilateral triangle in which the seal width XA increases from the center of the inner side portion 23 toward the 1 st seal portion 31, i.e., in the direction of the progress of peeling. The length of 1 side of the equilateral triangle is 10 mm.

The outer contour shape of the vapor flow seal 60 of the samples of examples 1 and 3 is a triangle in which the seal width XA decreases from the center of the inner side portion 23 toward the 1 st seal portion 31, that is, in the direction of progress of peeling. The length of 1 side of the equilateral triangle is 10 mm. The outer contour shape of the vapor flow seal 60 of the samples of examples 2 and 4 is a trapezoid in which the seal width XA decreases from the center of the inner portion 23 toward the 1 st seal portion 31, i.e., in the direction of progress of peeling. The length of the upper bottom of the trapezoid is 10mm, the length of the lower bottom is 20mm, and the height is 10 mm.

The samples of comparative examples 1 to 4 and examples 1 and 2 had a dimension of 1mm in the 1 st direction of the steam outlet. The samples of comparative examples 1 to 4 and examples 1 and 2 had a dimension of 3mm in the 2 nd direction of the steam outlet. The samples of comparative examples 5 to 8 and examples 3 and 4 had a dimension of 3mm in the 1 st direction of the steam outlet. The samples of comparative examples 5 to 8 and examples 3 and 4 had a dimension of 1mm in the 2 nd direction of the steam outlet.

In order to evaluate the seal peeling performance, it was visually confirmed whether or not the entire steam flow-through seal portion 60 was peeled off when the closed steam flow-through flat bag 10 was heated by the heating means. The state where the entire steam flow seal portion 60 is peeled off is a state where the portions of the 1 st sheet 21 and the 2 nd sheet 22 constituting the inner portions 23 are not joined. The steam flow seal 60 was evaluated as good in seal peeling performance when peeled off entirely, and as poor in seal peeling performance when at least a part of the steam flow seal 60 was not peeled off.

In order to evaluate the steam flow performance, it was visually confirmed whether or not the content C did not leak from the steam outlet 70 when the steam was discharged from the steam outlet 70 by heating the closed steam flow-through flat bag 10 by the heating means. The state where the content C does not leak from the steam discharging portion 70 means a state where the content C does not adhere to the surface of the 1 st sheet 21 and the periphery of the steam flow type flat bag 10. The state where the content C leaks from the steam discharge portion 70 means a state where the content C adheres to at least one of the surface of the 1 st sheet 21 and the periphery of the steam flow type flat bag 10. The number of tests was 3. The content C is the food material of beef rice. The food material of the beef rice comprises beef, vegetables and soup. The weight of the content C was 80 g. The power of the microwave oven was 600W. The heating time of the microwave oven was 1 minute and 20 seconds.

"○" in the items of the seal peeling performance in fig. 8 indicates that the entire steam flow seal 60 is peeled off, and "x" indicates that at least a part of the steam flow seal 60 is not peeled off, "○" in the items of the steam flow performance in fig. 8 indicates that the content C does not leak out when the steam is discharged from the steam discharge portion 70, and "x" indicates that the content C leaks out when the steam is discharged from the steam discharge portion 70.

According to the steam flow type flat bag 10 of the embodiment, it was confirmed that the entire steam flow seal part 60 was peeled off and the content C was hardly leaked when the closed steam flow type flat bag 10 was heated by the heating means. Further, it was also confirmed that, when the steam discharge portion 70 had a shape extending in the direction of progress of peeling, the entire steam circulation seal portion 60 peeled off and the content C was less likely to leak.

(modification example)

The above embodiments are illustrative of the manner in which the steam-flow-through flat bag according to the present invention can be employed, and are not intended to be limiting. The steam flow type flat bag according to the present invention can be obtained by combining at least 2 modifications of the above-described embodiments, which are not inconsistent with each other, as shown below.

The structure of the steam flow seal 60 can be changed as desired. Fig. 9 shows an example of a modification of the steam flow seal 60. The steam flow seal 60 includes a first peeling portion 61 and a second peeling portion 62. The profile shape of the first peeling portion 61 is, for example, a semicircle. The outer contour shape of the rear peeling section 62 is an isosceles triangle in which the seal width XA decreases in the peeling development direction. The position where the steam discharge part 70 is provided is arbitrary inside the outer contour of the steam flow seal part 60. According to example 1, the steam discharge portion 70 is provided across the pre-peeling portion 61 and the post-peeling portion 62. According to example 2, the steam discharge portion 70 is provided only in the rear peeling portion 62 in the steam flow seal portion 60.

Fig. 10 shows another example of a modification of the steam flow seal unit 60. The steam flow seal 60 includes an unsealed portion 71, and the unsealed portion 71 is provided to surround the periphery of the steam discharge portion 70. The unsealed portion 71 is a portion where the 1 st sheet 21 and the 2 nd sheet 22 inside the outer contour of the steam circulation seal 60 are not joined. When the steam flow seal 60 is formed by joining the 1 st sheet 21 and the 2 nd sheet 22 to form the unsealed portion 71 after the steam discharge portion 70 is formed on the 1 st sheet 21, thermal contraction around the steam discharge portion 70 in the 1 st sheet 21 can be suppressed. Therefore, the steam discharge portion 70 is easily maintained at a predetermined size.

Description of the reference numerals

10: steam flow through flat bag

10C: accommodating space

20: sheet material

23: inner side part

30: sealing part

50: guide part

60: steam circulation sealing part

61: first stripping part

62: rear peeling part

70: steam discharge part

C: content(s) therein

Claims

1. A vapor flow through flat bag wherein,

the vapor flow-through flat bag has:

a sealing portion that seals the sheets that are stacked so as to form a housing space for housing the contents;

a steam circulation seal portion that joins portions of the sheet materials to each other so as to be discontinuous with the seal portion, at an inner portion of the sheet material that is a portion inside the seal portion; and

a steam discharge portion formed in the steam circulation seal portion so as not to communicate the housing space with the outside in a state where the steam circulation seal portion is not peeled and so as to communicate the housing space with the outside in a state where the steam circulation seal portion is peeled,

the steam circulation seal portion includes: a peeling-first portion including a portion that is peeled first at the steam flow seal portion in accordance with an increase in pressure of the housing space; and a rear peeling portion included in a portion which is peeled off last at the steam circulation sealing portion,

the width of the post-peeling portion in a direction different from the direction of progress of the peeling of the steam circulation seal portion is smaller than the width of the pre-peeling portion in a direction different from the direction of progress of the peeling.

2. The vapor flow-through flat bag of claim 1,

the rear peeling portion is formed so as to decrease in width toward the front side in the direction of progress of the peeling.

3. The vapor flow-through flat bag according to claim 1 or 2, wherein,

the steam discharge portion includes a slit or a hole penetrating one of the overlapped sheets, and is formed to extend in a direction in which the peeling progresses.

4. The vapor flow general flat bag according to any one of claims 1 to 3,

further has a guide portion constituting a guide for separating the sheet and a part of the seal portion to open the housing space closed by the seal portion,

the steam circulation seal portion is provided at a portion of the sheet material separated by the guide portion.

5. The vapor flow general flat bag according to any one of claims 1 to 4,

the size of the steam discharge part in the development direction of the peeling is greater than or equal to 12.5% of the size of the steam circulation seal part in the development direction of the peeling.

6. The vapor flow general flat bag according to any one of claims 1 to 5,

the size of the steam discharge part in the development direction of the peeling is less than or equal to 62.5% of the size of the steam circulation seal part in the development direction of the peeling.

7. The vapor flow general flat bag according to any one of claims 1 to 6,

the container further comprises the content contained in the containing space.